ES-3100 Series Switch Support Notes
All contents copyright (c) 2006 ZyXEL Communications Corporation.
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QoS ACL Flow Example
Here is another scenario to help you understanding the flow of ACL. There
are totally 4 rules.
First rule contains the following:
• When there is traffic from Layer 2 VLAN ID = 4094
Any matched packet will be set the Priority to 7
Second rule contains the following:
•When there is traffic from Layer 2 Source MAC address = 00:00:00:00:00:01
Any matched packet will be set the Priority to 6
Third rule contains the following:
•When there is traffic from Layer 2 Source Port = 1
Any matched packet will be set the Priority to 5
Fourth rule contains the following:
•When there is traffic from IP source address = 192.168.1.100/32
Any matched packet will be set the Priority to 4
The above four rules are conflicting together since you can have traffic
coming from port 1 and also come with a source IP address of 192.168.1.100.
When two or more rules match a packet and the resulting actions are
conflicting (Set to different priority value), a higher layer rule has priority over
lower layer rule. In this case, the action of the fourth rule (Layer 3) is carried
out because the other rules are only up to Layer 2. Although VLAN, MAC, Port
are all belonging to Layer two, their carrying out priority would be
VLAN>MAC>Port.
In conclusion, every parameter (or rule) in the packet header has a weight.
The deeper the parameter in the packet header, the higher the weight is.
Further more, the deeper parameter in the packet header has much more
